Truism

A truism is a claim that is so obvious or self-evident as to be hardly worth mentioning, except as a reminder or as a rhetorical or literary device, and is the opposite of falsism.

In philosophy, a sentence which asserts incomplete truth conditions for a proposition may be regarded as a truism. An example of such a sentence would be "Under appropriate conditions, the sun rises." Without contextual support – a statement of what those appropriate conditions are – the sentence is true but incontestable. A statement which is true by definition (for example, the Lapalissade "If he were not dead, he would still be alive") would also be considered a truism.

The word may also be used with a different sense in rhetoric, to disguise the fact that a proposition is really just an opinion. Similarly, stating an accepted truth about life in general can also be called a truism.

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